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Brake system series 2 roadster

70sIIroadster

Freshman Member
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Need help on a few questions about a series 2 roadster We're trying to bring back from a long slumber.

(1) Is there a series 2 manual? We only have a series 1 manual.

(2) Does anyone have an overall operational view of the Braking system on the series 2? We are experiencing very hard pedal pressure to stop the car. We have checked the vacumn all the way to the booster servo. There appears to be vacumn at the servo. The servo system appears to not be leaking. But still high pedal pressure. Having no idea how the system works it is difficult to trouble-shoot the system. There appears to be two master cylinders. One with the brake pedal system and one off the servo. We think the problem is in one or both of the master cylinders.
Can someone give us some guidence?

(3) The revcounter has also stopped working. The series 1 cars used a closed system with a small generator attached to a cam. The series 2 appears to use a pulse system. But again no diagram so we have no idea where to look. Can someone help here?

Any feed back would be helpful to some "shade tree" mechanics in the flat lands of Kansas.
 
The current series I 3.8 manual has a series II addendum that has all the information and schematics that you need. If you dont have this version you need it. From what you have said, the failure is the brake servo unit. The two brake units on the drivers side of the engine compartment are a master unit and a servo unit. They are a medium undertaking to remove from the car and a far more challenging excercise to rebuild properly. I recommend you remove them from the car and send them to a rebuilder such as Apple Hydraulics or White Post Restorations. You really dont want to repeat taking the units out of the car a second time around. I also recommend you rebuild both units even though the indications point to the brake servo.
Best regards, Jack.
 
Tnx for the info and advice. Will take your advice on the rebuild of the two master cylinders.

70sII roadster /ubbthreads/images/graemlins/hammer.gif
 
Another critical thing to check is tha amount of vacuume the engine is producing. My Series I was runing and racing fine but the pedal pressure to stop the car was terrible, I mean stopping was not possible! I tried everything in checking the brake system and everything seemded to be OK. However, upon measurement, the engine was only producing 5 inches of vacuume. The system needs at least 12-15 inches of vacuume to work at all and a non-race/stock engine will usually produce about 20+ inches of vacuume.

If you are jsut checking vacuume by seeing if it exists, that will not be enough, you need to measure it. I would do that first before tearing everything else out. A new engine/engine rebuild was the ultimate answer to my problem.

GHregJ
 
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